SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fcc3d43ebc2c6454e5999a020a45d3bee909e7c5cea7832efea7bdf87a47c39e' 
  AND token = 'cYgQT32nP7i2TT6KZzx75teTP16wI1quHj180sbyHk8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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