SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8eb271b89e8a4c2d8d4fbb1c787fad4256a70324c00e27b2a1c008916d88dfc7' 
  AND token = 'I2E0IVFj3to1jyR5vX80coFEkpSUinvfLkIQQCJzLO4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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