SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '761369f6a84be46c6df69221ab9202e4ee38c07d3edecca1c1f387d6c583f96a' 
  AND token = 'X+Pe1dYgZzYKN38Iw+B/VyF6T4LDQD2In4NCJEckn/M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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