SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3c0d0cae768d14cc30a7b89dac9a77bc8917e9737ce44db10166f7b17ab2c436' 
  AND token = 'yRskdOB8tmUM0LlHrIEFIStmvZnizNx7vlMoZsUmut8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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