SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3f929630b26aac2da6c58c52d36a4bf1249a86bcfdeec3e50b781f6a94821132' 
  AND token = 'hDSuQZL/j4sgu61OymjuqV1ulw94a2LqDKGDiwEjnRY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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