SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd0a269a03bf396595c1d2a5c63590d14bfd6718c185816cede8afbf922f9742' 
  AND token = 'm3aio4YqVelnixShoxQjlOpsaZcDuKWvTEFHdqDrUv4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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