SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fac4c7bd42082ff0c8c00d14a6d168051b2579a81d4d16e40e7afb86aa843941' 
  AND token = 'U2Rx3zykFVbzgYHfgpxRHfCsIenCLcCRm6DLUCx78Mk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}