SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70fefae078bdf599df61e552dc6adad5ad57f4945c1740600d2732555ba7320a' 
  AND token = 'J8U1K0xuZphqFr9XRJpZkpnm9IJVVCUZdRa/+2yPK74=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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