SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fe43d1e83f6a2155a318371bc884a7c9459bc1368c48b53f9fad24099fbaa26b' 
  AND token = 'BAZlOPKRR5IMSuAoWbq7nFPuvac1Q/LgUb/Em+UfG4c=' 
  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"
    }
  }
}