SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd349615ac6bcf5b2e66c19551877ad9e97eb35a2e36604c2c85018bd4d5c5929' 
  AND token = 'bAFewTAb9emcAPI34oHNp2nv9dh8n6PYxbvaoy9Oh9o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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