SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c162cab104b7c8b85c1fcd022cb9bb05637adef76794d2899dc632815778f7a0' 
  AND token = '0LdS/PA+f8b1v6oDe7HOP5ffFSjdTLEZtr7dR2zDrck=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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