SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3a39f8b3a71fb8b6a6adf2ede6300c5454417d00056301882e1ef3f376629a6e' 
  AND token = 'vw14Vbzc6DyWEKR5oDFWswrer/WKqXaDSCy/SqJAVh4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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