SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e60d08ae37b6ff81bac05608adbc9feede5880412f33a3ea06321fbed75e7dab' 
  AND token = 'rFx7T3XpaBjKv2deazl64ufOvZz03nrsETcguf+YMD0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}