SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a26e51a1628357a0b011bc068a96d4e526836df7f14d3dbff6c3682eb090383e' 
  AND token = 'w6UTacvVqCYGT1zNK2Rlap7SXmKaewPFiE4Z7lGLKJs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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