SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59f60ed0f1cce33ab2a44f6676450099c14b87cf0f25665b3f53bf8f508cc537' 
  AND token = 'cMcdl6r0bzz/zj7QyLC4/IZWCrZ7zLrQqonfkz58y9c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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