SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4217660926f0f0bf43a005213ad4a32b2a2692c0eee1a60bc771e1f54e48f331' 
  AND token = '9SE9VzyztTkE3IF9SCpUXh9ll3oFHlRlu8+Gp6Psr5I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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