SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2caef1c53625bf59d60661789857c3e5f4d81f31d4923a81827c99d556334121' 
  AND token = 'dsMX6UrcO77a/eoUVAR7KXuTguQ7G34rvlG08QW40NQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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