SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60d2a363bf1de598577bdedaf699e1ff8ec92802f9e86da80e6abff47dc44356' 
  AND token = 'Xj0u+g1PNHjZ69CPCMZ+2Zhj6zXYvE4ROdnezTUlJJs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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