SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab7c055f31266dce6597888a27c2dc147c0d079f111e9969c25271167d399bc9' 
  AND token = 'CDk2ZXTJTarFgRLur8Tc0KnFz6t8l9IjIudjkUoiYfY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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