SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb24819f826f12c26bac7e6dc65582e28dc1443c5cc1554a389b087b3375e872' 
  AND token = 'w4I7A0wSMDCFZm0zgugdo40+6Mp91ywv/p7RyDV3JDo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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