SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a2b67db3c53b0b4c3638d8ecc997882180906004644c75aa6fcc29c952e726f6' 
  AND token = 'BkXBgM6Ha1/fHAfLjrBr5EHCBDZFv6hv8C9Nd14kBfA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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