SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f4aaf2266d64965ed46815068bbc31348830768d25ae1e62a899b4efbf7e9a65' 
  AND token = 'fxxgusfmXipcOxeyys0L7QsnrZzj8j7n3xu1Xr3qt8E=' 
  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"
    }
  }
}