SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8b82cd120bb4ad03767cc13480d9b2109087e372c697fd61c7beb4df77a73048' 
  AND token = 'XD3to71t4G4S174hfv7rCEqiomWGpdiewAEJW0Zd4LQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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