SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '99d29611194304bb00c63099b716e6b07199bf37a0a2485036f20b1cc71326a1' 
  AND token = 'XNEHoWwFDB4nPOMVkNKdRjrzabuDmIQvCDMpSloFqH0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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