SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '855e741dbb85ec13a29f3fc563aa10580f2807584e18629f9d59c3be0abecdc5' 
  AND token = 'xPGNOKxyvB39H8EyGLsJggF4EDydGQUQ85qagGfYt94=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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