SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ffe2c349339c73ea5c22d19c3f804b86d9322e52e563e9fd48610d96fe1f6cad' 
  AND token = 'uz9Wb8LheyE6JwpPZN2MCK8BI4qCmKDLyoqzNinW/nQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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