SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b70865b3ea811e13acd3f00c6746159a589e61d1dac9d3780a75c12f4d2d024' 
  AND token = 'Qzg/LF7OPv4gT7zVPgpYWg2BAzbm2jXZVujOdMq/zJ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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