SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d9723231fd1c949f074e0952affe6967589e6d0798b66626ba18697f4aceba0' 
  AND token = 'vwTw3rXIPFG1zjPgihKYJl+0/MnXaHlffNmd+b/8E+I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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