SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18ea2623be3215ede3aec4c157efcb78a1e5eac314b54e5bac2668edd5e8384f' 
  AND token = 'JF0V75rmEi2gTFksSKDGoIJ9jeE/QQDD32kjSiZ01OA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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