SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3b4093a2657711b613d28d25af91b62062f1a1773b8ec7bb31caeb001928195' 
  AND token = 'nWtWft0Ts+48wJjgy6eOztEIoGDtYbesvcL+ev9HaD8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}