SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c19d9980dff3f59587fab8582c36ab8992a27c1392973fb5508c12a0c67b421a' 
  AND token = 'EhtKw4KCh9ch47OdtS9tcnG0nDRGdy3WezPEHUQOIIs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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