SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5e779cd4771a354b1a3f7c55edf61a1c33d79a99029aa7c0b0581554f2e3a592' 
  AND token = 'Ax+UfrTSCSShiG/GkRdcF8EAPJbVo8NDx1fzfkFe6SY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}