SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '787d83529fc0e5bea409b0d31763c4303e98e74cb599d4c0a614de87d981ddec' 
  AND token = 'ImCp9IkEvQfjMvGQfYpikGrnZ49j92ctk2zSB1u0TLI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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