SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d37fd2c54acf09947d9aa67715048bcaf55139d5f8cf3a4f112b2791bd75a1c' 
  AND token = 'nKbmQdBBnmSRWK5WHbURXXbUBIGN732+NyeXJR544e0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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