SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b201873dd3a162688a3950f7e107cc450d23f024351a31ffd38f7d08c7304fb0' 
  AND token = 'v+j06SFu9XhCAgj1wEkkL8YcQh1dfBb8fQFKi0gF4BI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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