SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2d05bac63d41aaf3896ef7541dda00c2d553c88028f6658bb5ebb3e9880f2ec' 
  AND token = 'PjOMEoSB+RId6+WuqtuRgT+OzRFCBqTkRD43S2bQJxs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}