SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f754f0a0639e29d2498b6abf8de1ca26d8fe459d75635f2046b14ee0afd8c183' 
  AND token = 'JywEZJYu/2GagkW8qOO4qj35HjmmQqoR+etNGARcW0o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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