SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8e5283747d52e14d16f714f6da3181888a5f4bbe067c2fb78df7538412b25796' 
  AND token = 'hWv4wKIQ/R7Cn+bl96X4uIBQ5pqicJIcrvpYThWfR0o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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