SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4dcbfbec512246bc1c6e983ae88508c196116f64d33d8339a382678ca7765c36' 
  AND token = 'cHDpzaseyZRwuOzV3Zh+RyoE83EEsa6dG/tOOL1Qm8U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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