SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4722487be9a235b6b3a1f91f42aec3ed7a7597e928418d62a4dd04dddbfdad7e' 
  AND token = 'fyvkZCH8hEyFarSbBh3gA/oEb+NbzPksgoBkJalrkwM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00071

JSON explain

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