SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0b11edd4fc8a9d558e29390a779246e357c42f39f546ec9448ec983f0fa92e3' 
  AND token = 'gZxUH+8qABxKbnInGVJ2AvAbMJw5ESIJrLtq9In2d/M=' 
  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"
    }
  }
}