SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bd3fc9b4c3e409a06c7713eac20a3a6df542b90cb638bc1a510ec33fbf2c7479' 
  AND token = 'uXpbv2oRuXVJsNzfHduHyTSpZp/+m/0uewaHrk3EyHE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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