SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ebccbfc614377dd6a7140e17678f53201fb56f6ba62184cf48b6c5177ab264ce' 
  AND token = 'pyVvUmy1DlQwRDGAryAFE6/oTNpDfnouyBZ6ej3cZfs=' 
  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"
    }
  }
}