SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c02d1daa4287f6c71b4c5338244a0b9e5673ff4a5ed70edeffb72ca2ee97ae40' 
  AND token = 'Sx5yORzTuiB+5wJJ8shs747ZwQ7VlTRxPNUVXNiKuWw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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