SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b3697db46af73ede93f5e1a9682a00246e21c5a649508329be5b40aeacad69e' 
  AND token = 'v/6J7bV8hHIqn9/lUduuTOPQru651myHbi1nH00D0s8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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