SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b7c035351972ed8c572f3dfd2fea95bc83f8b693b00f914445c07367b29c4ffc' 
  AND token = 'mouHCArFaopCzCSzzk41H53+HI5m6H+YS9/QokwJnPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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